Extensible bracket.



P. C. BURNS.

EXTENSIBLE BRACKET.

APPLICATION FILED SEPT.29.19I6.

1 ,274,001 Patented July 30, 1918.

M- Kw 3 mm c. BURNS, or 'cmcaoo, minors.

EI'IENSIBLE nnacxn'r. v

To all whom it may concern:

Be it known that I, Pm'nn GJBURNS, a

citizen of the United States of America, and

resident of Chicago, Cook county, Illinois, have invented a certain new and useful Improvement in Extensible Brackets, of which ,the followin is a specification.

panying drawings in which. I have illustrated one embodiment of my invention.

. Figure 1 is a side elevation of a bracket embodying my invention;

Fig. 2 is an enlarged detail partly in section; and Fig. 3 is a rear elevation partly in section.

,My improved bracket consists of two series of links 4 and 5 pivoted together so as to form a well known type of bracket known as lazy tongs, the construction being such that these links can be extended or contracted as desired. The, outer end of the series of links 4 is pivotally connected to a plate'6 while the outer ends of the seriesof links 5 is pivotally connected to a'swingr ing link 7, the opposite end of which swinging link is pivotally connected to the'lower portion of the plate 6. This plate carries a suitable clamp 8 which is adapted to gri the tubular standard 9 of a telephone des set or other article which it is desired to support. The upper edge of the plate 6 engages immediately beneath the bead 10 formed on the upper part of the tubular support 9. In this manner this support is prevented from sliding downward in the clamp and thus this clamp is prevented from coming into engagement with the switch hook and thus interfering with the operation thereof.

The iimer end of the series of links 5 is pivotally connected to one arm of a T- shaped member 11. The inner end of the series of links 4 is-tfiiivotally connected to a, swinging link 12, e opposite end of this specification of Letters Patent.

Patented July so, 1918.

Application m September 29,1910. 8ei'1a11I'o.122,800.

swlnging link being connected to the opposite end of the cross bar of the T-member. ThlS T-member is pivotallymounted on the bolt 13 which passes through and is supported by two upwardly extending bars 14,"

1 5. Secured to the lower ends of these bars 1s a suitable clampin member 16 which is adapted to slip over t e post 17 for supportmg the bracket. These two bars 14, 15 are held together at their upper ends by means of bolts and nuts 18 by which means the distance between these two bars can be adusted so as to vary the pressure exerted upon the vertical member of the T. A suitable spring 19 is secured at itsupper end to the inner'end of the T-member and its lower end is secured to the clamp 16..

This spring is so adjusted as to exert a downwardtpull on the inner end of the T- member an gravity exerted by the telephone desk set carried by the outer end of the bracket.

When the bracket is in contracted position,

- as shown in full lines in Fig. 1, the tension of the spring over-balances the-desk set, but when the bracket is expanded, as shown in dotted lines in Fig. 1, the increased leverage enabl'esthe desk set to substantially counterin this manner operates to substantially counter-balance the .force of balance the tension exerted by the spring so that the bracket will remain 1n any angular position in which it is placed. In order that the bracket may not move too freely about its pivotal point, the bars 14 and 15 are so adjusted as to exert a certain amount of pressure on the T-bar and thus produce suflicient friction to retard the movement of the bracket. Without this frictional engagement it is found that the desk set moves so freelyabout its pivot that it will not remain in a given position.. By means of such frictional engagement, however, the

tension of the spring can be so regulated that it. practically counter-balances the weight of the desk set when the bracket is in extended position, and with such con-,

struction the bracket will be in a substantial state of equilibrium so that the desk set when raised or lowered willremain in thisposition. t

B means of theswinging links 7 and 12 at t e opposite end of the. azy tongs I am enabled to avoid the use of any sliding connections. The lazy tongs can be readily expanded or contracted and the spreading or contracting of the opposite ends is comall times maintained .in a state of equilibrium.

While I have illustrated and described one particular embodiment of my invention it will be understood-that I do not wish to be limited to the exact structure shown and described, but that various changes and modifications will readily suggest themselves to those skilled in the art and come within the scope of my invention.

What I claim as my invention is:

1. In a device of the class described, an extensible bracket pivotally mounted at its inner end a member supported on the outer end of said bracket, a 3 ring secured to the inner end of said bra'c et and exerting a downward tension thereon, and frictional means for retarding the pivotal movement of said bracket about its pivot.

2. In a device of the class described, a' support consisting of two arms suitably spaced apart, an extensible bracket pivotally mounted between said arms, means for drawing said arms together so as to frictionally engage. said racket and thereby dampen the movement thereof, a member carried by the outer end of said bracket, and spring means secured to the inner end of said bracket operating to substantially counter-balance said member carried by the outer end of said bracket.

3. In a device of the class described, a series of links forming a lazy tongs, a pivotally mounted T-member supporting the inner end of said lazy tongs, a clamping member carried by the outer end of said lazy tongs for supporting a telephone or the like and a spring connected to the inner end of said T-member for counter-balancing the weight of said telephone.

T-member for counter-balancing the weight of said telephone, a pair of arms between which said T-member 1s mounted, and means for producing a frictional engagement between said arms and member thereby re tarding the movement thereof.

5. In a device of the class described, an extensible bracket pivotally mounted at its inner end, said bracket consisting of two series of links, one series being-pivotally connected atits outer end to a supporting member, the other series being pivotally connected at its outer end to a swinging link, the opposite'end of which link is pivotally connected to said supporting member and a spring secured to the inner end of said .bracket and operating to counter-balance the force exerted on said bracket by said supporting member.

6. In a device of the class described,an extensible bracket pivotally mounted at its inner end, said bracket consisting of two series of links forming a lazy-tongs,- a member supported on the outer end of said bracket, a spring associated with the inner end of said bracket and operating to substantially counter-balance said member carried by the outer end of said bracket, and frictional means for retarding the pivotal movement of said bracket about its plvot.

Signed by me at Chicago, Illinois, this 22nd day of September, 1916.

PETER o. BURNS. 

